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EW Pistons

Started by alwyn, 08 Dec 2007 at 03:53

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Hi all,
A friend and fellow member of LDMCC but not of the forum suggested a recent experience he had with his EW Dougie was worth reporting here - so I relate the following on his behalf.

Said friend replaced the pistons of his EW motor with a pair made by JP Pistons which, it was purported, had been made specifically for the Douglas EW engine - the pistons subsequently seized in the bore after very limited use - upon dismantling and closer inspection and measuring it was found that the pistons had not been 'cam ground' but were of constant diameter.

Knowing that the LDMCC spares department have in the past provided and may still currently provide pistons made by JP Pistons to its members, my friend wondered (and has raised my curiousity too), if those pistons as provided are 'cam ground'? - can anyone else report similar seizures or failures due to having fitted pistons provided by JP Pistons that were not 'cam ground'?

Quotable Quote - "640 k should be enough for anybody"! - Bill Gates - 1981.


Alwyn, the experience I have had is that they work very well as long as you do not use the clearances they specify - they usually say 4 thou but we find 6-7 works fine

The pistons I have had from them have been cam ground as per specs

We have had problems with circlips from them though - they ares ometimes very sof and do not hold - with the obvious problems following !